SOIL CHARACTERISTICS AND SHEAR WAVE VELOCITY STUDY IN NORTH SULAWESI, GORONTALO AND CENTRAL SULAWESI

Abstract

The Sulawesi region has a high level of earthquake vulnerability because it is bounded by two major plates, the Eurasian plate and the Indo-Australian plate, which leads to several paths and faults scattered throughout the region, including the volcanoes in North Sulawesi Province, the Gorontalo fault in Gorontalo Province, and the Palu-Koro fault in Central Sulawesi Province. In North Sulawesi, Gorontalo, and Central Sulawesi, soil characteristics were studied utilizing the Horizontal and Vertical Spectral Ratio (HVSR) approach. The dominant frequency (f0), the amplification factor (A0), the seismic vulnerability index (Kg), and the shear wave velocity at a depth of 30 m (Vs30) were all measured in this study. According to the findings of this study, the distribution of dominant frequency values ranged from 0.6 to 17 Hz, the amplification factor ranged from 2.2 to 8.4, the seismic vulnerability index ranged from 0.2 to 41, and the shear wave velocity at the depth of 30 meters (Vs30) ranged from 226 to 519 m/s.